Add New Section to PE File

unit uAddSection;

//steve10120

interface

uses

  Windows;

function AddSection(szFileName:string; szNewSectionName:string; dwNewSectionSize:DWORD; dwNewSectionCharacteristics:DWORD):Boolean;

implementation

function Align(dwValue:DWORD; dwAlign:DWORD):DWORD;

begin

  if dwAlign <> 0 then

  begin

    if dwValue mod dwAlign <> 0 then

    begin

      Result := (dwValue + dwAlign) - (dwValue mod dwAlign);

      Exit;

    end;

  end;

  Result := dwValue;

end;

function LastSectionRaw(Sections: array of TImageSectionHeader):DWORD;

var

  i:    integer;

  Ret:  DWORD;

begin

  Ret := 0;

  for i := Low(Sections) to High(Sections) do

  begin

    if Sections[i].SizeOfRawData + Sections[i].PointerToRawData > Ret then

      Ret := Sections[i].SizeOfRawData + Sections[i].PointerToRawData;

  end;

  Result := Ret;

end;

function LastSectionVirtual(Sections: array of TImageSectionHeader):DWORD;

var

  i:   integer;

  Ret: DWORD;

begin

  Ret := 0;

  for i := Low(Sections) to High(Sections) do

  begin

    if Sections[i].Misc.VirtualSize + Sections[i].VirtualAddress > Ret then

      Ret := Sections[i].Misc.VirtualSize + Sections[i].VirtualAddress;

  end;

  Result := Ret;

end;

function AddSection(szFileName:string; szNewSectionName:string; dwNewSectionSize:DWORD; dwNewSectionCharacteristics:DWORD):Boolean;

var

  hFile:  DWORD;

  x, i, k:  integer;

  IDH:      TImageDosHeader;

  INH:      TImageNtHeaders;

  Sections: array of TImageSectionHeader;

  dwRead:   DWORD;

  bDataBuff:  array of Byte;

const

  szError:  string = 'Add Section Error';

begin

  Result := FALSE;

  if Length(szNewSectionName) > 1 then

  begin

    if Length(szNewSectionName) > 8 then

      szNewSectionName := Copy(szNewSectionName, 1, 8);

    hFile := CreateFile(PChar(szFileName), GENERIC_READ or GENERIC_WRITE, FILE_SHARE_READ or FILE_SHARE_WRITE, nil, OPEN_EXISTING, 0, 0);

    if hFile <> INVALID_HANDLE_VALUE then

    begin

      SetFilePointer(hFile, 0, nil, FILE_BEGIN);

      ReadFile(hFile, IDH, 64, dwRead, nil);

      if IDH.e_magic = IMAGE_DOS_SIGNATURE then

      begin

        SetFilePointer(hFile, IDH._lfanew, nil, FILE_BEGIN);

        ReadFile(hFile, INH, 248, dwRead, nil);

        if INH.Signature = IMAGE_NT_SIGNATURE then

        begin

          k := INH.FileHeader.NumberOfSections;

          SetLength(Sections, k);

          x := IDH._lfanew + 24 + INH.FileHeader.SizeOfOptionalHeader;

          for i := Low(Sections) to High(Sections) do

          begin

            SetFilePointer(hFile, x, nil, FILE_BEGIN);

            ReadFile(hFile, Sections[i], 40, dwRead, nil);

            Inc(x, 40);

          end;

          if INH.OptionalHeader.SizeOfHeaders >= (x + 40) then

          begin

            Inc(INH.FileHeader.NumberOfSections, 1);

            SetLength(Sections, INH.FileHeader.NumberOfSections);

            with Sections[INH.FileHeader.NumberOfSections - 1] do

            begin

              CopyMemory(@Name[0], @szNewSectionName[1], 8);

              Characteristics := dwNewSectionCharacteristics;

              PointerToRawData := Align(LastSectionRaw(Sections), INH.OptionalHeader.FileAlignment);

              SizeOfRawData := Align(dwNewSectionSize, INH.OptionalHeader.FileAlignment);

              VirtualAddress := Align(LastSectionVirtual(Sections), INH.OptionalHeader.SectionAlignment);

              Misc.VirtualSize := Align(dwNewSectionSize, INH.OptionalHeader.SectionAlignment);

            end;

            INH.OptionalHeader.DataDirectory[11].VirtualAddress := 0;

            INH.OptionalHeader.DataDirectory[11].Size := 0;

            Inc(INH.OptionalHeader.SizeOfImage, Sections[INH.FileHeader.NumberOfSections - 1].Misc.VirtualSize);

            SetFilePointer(hFile, IDH._lfanew, nil, FILE_BEGIN);

            WriteFile(hFile, INH, 248, dwRead, nil);

            SetFilePointer(hFile, x, nil, FILE_BEGIN);

            WriteFile(hFile, Sections[INH.FileHeader.NumberOfSections - 1], 40, dwRead, nil);

            SetLength(Sections, 0);

            dwNewSectionSize := Align(dwNewSectionSize, INH.OptionalHeader.FileAlignment);

            SetLength(bDataBuff, dwNewSectionSize);

            SetFilePointer(hFile, 0, nil, FILE_END);

            WriteFile(hFile, bDataBuff[0], dwNewSectionSize, dwRead, nil);

            CloseHandle(hFile);

            Result := TRUE;

          end;

        end

        else

          MessageBox(0, PChar('Bad PE signature.'), PChar(szError), MB_ICONEXCLAMATION);

      end

      else

        MessageBox(0, PChar('Bad MZ signature.'), PChar(szError), MB_ICONEXCLAMATION);

    end

    else

      MessageBox(0, PChar('Error opening file.'), PChar(szError), MB_ICONEXCLAMATION);

  end;

end;

end.

if AddSection('hellovb6.exe', '.test', 100, IMAGE_SCN_MEM_EXECUTE or IMAGE_SCN_MEM_READ or IMAGE_SCN_MEM_WRITE) then

  MessageBox(0, PChar('Section added successfully.'), PChar('Success'), MB_ICONINFORMATION);